The WFP also accepts direct (money) donations from individual donors.
TBH, I'm not sure it's possible to donate either to this or to "World Central Kitchen" and ensure your donation goes only to [food for] Gaza, since they run world-wide programs.
FWTW, WCK claims to serve around 350,000 meals per day in Gaza. The WPF around 300,000 it seems, but that probably doesn't include parcels.